Canned tuna is America’s favorite fish. But regrettably, it’s also been the most common source of mercury in our diets. Some studies have linked even low-level mercury exposure in pregnant women and young children to subtle impairments in hearing, hand-eye coordination, and learning ability.america’s favorite fish. but regrettably, it’s also been the most common source of mercury in our diets. consumer reports’ latest tests show there’s still cause for concern. “isaac, you want some crackers?” jodi seubert is expecting her third child. she isn’t eating tuna because she’s concerned about possible mercury contamination. she also worries about her kids. “things you put in your body will, you know, affect the growth and development of your baby’s brain, of their bones, their whole body system, so i guess you think about that for your younger kids, too.” “some studies have linked even low-level mercury exposure in pregnant women and young children to subtle impairments in hearing, hand-eye coordination, and learning ability.” consumer reports tested two types of tuna at an outside lab – both albacore and light tuna – 42 samples in all. “every sample of tuna we tested had measura